(1) Field of the Invention
The present invention relates to a process and a device for the detection of a coming interposition of a mask between an aircraft and a target, particularly in a laser-guided weapon firing system.
(2) Description of the Prior Art
A laser-guided weapon firing system makes use of an aircraft carrying weapons fitted with homing heads sensitive to the reception of infra-red radiation. This aircraft is also fitted with an automatic target tracking system, in order to slave the aiming direction on the one hand and the direction of radiation of an infra-red transmitter located in the aircraft on the other hand, to the target direction. As this radiation is then reflected by the target, the homing head can, once the firing has been completed, slave its direction onto that of the target all the way along the path travelled by the weapons to the target.
The problem then arises of the possibility of an interposition of obstacles (such as hills, etc.), commonly called "masks", between the illuminating aircraft and the target, which would interrupt the reception of the infra-red radiation by the weapon's homing head, and because of this would prevent the system from functioning correctly.